5,719 research outputs found

    An overview of the literature concerning the oceanography of the eastern North Atlantic region

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    An overview of the main oceanographic features of the eastern North Atlantic boundary, with emphasis toward the upper layers, is presented. The principal features discussed are: water mass boundaries; forcing by wind, density and tides; topographic features and effects; fronts; upwelling and downwelling; poleward flows; coastal currents; eddies. The occurrence and spatial and seasonal variability of these features is described in five regional sections: Celtic Sea and western English Channel; Bay of Biscay; western Iberia; Gulf of Cadiz; northwest Africa. This paper is intended to provide a base of physical oceanographic knowledge in support of research in fisheries, biological and chemical oceanography, and marine biology

    Using a genetic algorithm to optimize a data-limited catch rule

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    Many data-limited fish stocks worldwide require management advice. Simple empirical management procedures have been used to manage data-limited fisheries but do not necessarily ensure compliance with maximum sustainable yield objectives and precautionary principles. Genetic algorithms are efficient optimization procedures for which the objectives are formalized as a fitness function. This optimization can be included when testing management procedures in a management strategy evaluation. This study explored the application of a genetic algorithm to an empirical catch rule and found that this approach could substantially improve the performance of the catch rule. The optimized parameterization and the magnitude of the improvement were dependent on the specific stock, stock status, and definition of the fitness function. The genetic algorithm proved to be an efficient and automated method for tuning the catch rule and removed the need for manual intervention during the optimization process. Therefore, we conclude that the approach could also be applied to other management procedures, case-specific tuning, and even data-rich stocks. Finally, we recommend the phasing out of the current generic ICES “2 over 3” advice rule in favour of case-specific catch rules of the form tested here, although we caution that neither works well for fast-growing stocks

    Effects of exercise intensity on vascular and autonomic components of the baroreflex following glucose ingestion in adolescents.

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    This is the final version. Available from the publisher via the DOI in this record.PURPOSE: To investigate the effects of an oral glucose tolerance test (OGTT) on baroreflex sensitivity (BRS) in a sample of healthy adolescents, and how acute exercise bouts of different intensities alter the effects of the OGTT on BRS. METHODS: Thirteen male adolescents (14.0 ± 0.5 years) completed three conditions on separate days in a counterbalanced order: (1) high-intensity interval exercise (HIIE); (2) moderate-intensity interval exercise (MIIE); and (3) resting control (CON). At ~ 90 min following the conditions, participants performed an OGTT. Supine heart rate and blood pressure were monitored continuously at baseline, 60 min following the conditions, and 60 min following the OGTT. A cross-spectral method (LFgain) was used to determine BRS gain. Arterial compliance (AC) was assessed as the BRS vascular component. LFgain divided by AC (LFgain/AC) was used as the autonomic component. RESULTS: Although non-significant, LFgain moderately decreased post-OGTT when no exercise was performed (pre-OGTT = 24.4 ± 8.2 ms mmHg- 1; post-OGTT = 19.9 ± 5.6 ms mmHg- 1; ES = 0.64, P > 0.05). This was attributed to the decrease in LFgain/AC (pre-OGTT = 1.19 ± 0.5 ms µm- 1; post-OGTT = 0.92 ± 0.24 ms µm- 1; ES = 0.69, P > 0.05). Compared to CON (Δ = - 4.4 ± 8.7 ms mmHg- 1), there were no differences for the pre-post-OGTT delta changes in LF/gain for HIIE (Δ = - 3.5 ± 8.2 ms mmHg- 1) and MIIE (Δ = 1.3 ± 9.9 ms mmHg- 1) had no effects on BRS following the OGTT (all ES < 0.5). Similarly, compared to CON (Δ = - 0.23 ± 0.40 ms µm- 1) there were no differences for the pre-post-OGTT delta changes in LF/gain for HIIE (Δ = - 0.22 ± 0.49 ms µm- 1) and MIIE (Δ = 0.13 ± 0.36 ms µm- 1). CONCLUSION: A moderate non-significant decrease in BRS was observed in adolescents following a glucose challenge with no apparent effects of exercise.Science Without Border

    The collective value of 'me' (and its limitations): Towards a more nuanced understanding of individual and collective coping with prejudice

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    AcceptedArticleThis is the peer reviewed version of the following article: Becker, J. C., Barreto, M., Kahn, K. B. and de Oliveira Laux, S. H. (2015), The Collective Value of “Me” (and it's Limitations): Towards a More Nuanced Understanding of Individual and Collective Coping with Prejudice. Journal of Social Issues, 71: 497–516, which has been published in final form at doi: 10.1111/josi.12125. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Within the social identity tradition, individual and collective responses to social disadvantage are typically seen as mutually exclusive. The current study (N = 120) provides a more nuanced understanding of individual and collective responses to social disadvantage by examining the ways in which women anticipate responding to ‘daily sexism’. We test how responses are independently related to ingroup identification, disidentification, and perceived ingroup homogeneity. Results show that women favor confronting sexism over inaction, even if that involves disparaging the ingroup. Specifically, women expect to engage in both individual and collective strategies in response to a sexist statement. Identification with women was positively associated with both collective and individual (non-group disparaging) responses, but only collective responses related to broader intentions to engage in collective action for social change. Finally, perceived group homogeneity uniquely increased agreement with the sexist statement, endorsement of inaction, and group-disparaging responses. Theoretical and practical implications are discussed.German Research FoundationPortuguese Foundation for Science and Technolog

    Oxidative stress in the brain and arterial hypertension

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    Universidade Federal de São Paulo, Dept Physiol, BR-04023060 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Physiol, BR-04023060 São Paulo, BrazilWeb of Scienc

    Exploring a relative harvest rate strategy for moderately data-limited fisheries management

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    Moderately data-limited fisheries can be managed with simple empirical management procedures without analytical stock assessments. Often, control rules adjust advised catches by the trend of an abundance index. We explored an alternative approach where a relative harvest rate, defined by the catch relative to a biomass index, is used and the target level derived from analysing historical catch length data. This harvest rate rule was tested generically with management strategy evaluation. A genetic algorithm was deployed as an optimisation procedure to tune the parameters of the control rule to meet maximum sustainable yield and precautionary management objectives. Results indicated that this method could outperform trend-based strategies, particularly when optimised, achieving higher long-term yields while remaining precautionary. However, optimum harvest rate levels can be narrow and challenging to find because they depend on historical exploitation and life history characteristics. Misspecification of target levels can have a detrimental impact on management. Nevertheless, harvest rates appear to be a suitable management option for moderately data-limited resources, and their application has modest data requirements. Harvest rate strategies are especially suitable for stocks for which case-specific analyses can be conducted

    Risk equivalence in data-limited and data-rich fisheries management: An example based on the ICES advice framework

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    Fisheries management needs to ensure that resources are exploited sustainably, and the risk of depletion is at an acceptable level. However, often uncertainty about resource dynamics exists, and data availability may differ substantially between fish stocks. This situation can be addressed through tiered systems, where tiers represent different data limitations, and tier-specific stock assessment methods are defined, aiming for risk equivalence across tiers. As case studies, we selected stocks of European plaice, Atlantic cod and Atlantic herring, where advice is provided by the International Council for the Exploration of the Sea (ICES). We conducted a closed-loop simulation to compare risk equivalence between the data-rich ICES MSY rule, based on a quantitative stock assessment, and the revised data-limited empirical management procedures of the ICES advice framework. The simulations indicated that the data-limited approaches were precautionary and did not lead to a higher risk of depletion than the data-rich approach. Although the catch based on generic data-limited approaches was lower, stock-specific optimisation improved management performance with catch levels comparable with the data-rich approach. Furthermore, the simulation indicated the ICES MSY rule can fail to meet management objectives due to increased depletion risk when management reference points are set suboptimally. We conclude that the recent revisions of the ICES system explicitly account for risk equivalence for data-limited fisheries management and are a major step forward. Finally, we advocate further consideration of simple empirical management procedures irrespective of data limitations due to their ability to meet fisheries management objectives with greater simplicity

    The utility of the reperfusion rate of tissue oxygen saturation as a measure of vascular endothelial function in adolescents: reliability, validity and sensitivity.

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    This is the final version. Available from Frontiers Media via the DOI in this record. Data availability statement: The raw data supporting the conclusion of this article will be made available by the authors, without undue reservation.Introduction: The near-infrared spectroscopy (NIRS)-derived reperfusion rate of tissue oxygen saturation (slope 2 StO2) may provide a surrogate measure of vascular function, however, this has yet to be examined in a paediatric population. This study investigated in adolescents: 1) the between-day reliability of NIRS-derived measurements; 2) the relationship between slope 2 StO2 and macro- (flow-mediated dilation, FMD) and microvascular (peak reactive hyperaemia, PRH) function; and 3) the effect of high-intensity interval exercise (HIIE) on slope 2 StO2, FMD, and PRH. Methods: Nineteen boys (13.3 ± 0.5 y) visited the laboratory on two occasions, separated by ∼ 1 week. On visit 1, participants underwent simultaneous assessment of brachial artery FMD and slope 2 StO2 and PRH on the internal face of the forearm. On visit 2, participants completed a bout of HIIE with slope 2 StO2, FMD and PRH measured pre-, immediately post- and 1.5 h post-exercise. Results: Slope 2 StO2 showed no mean bias (p = 0.18) and an intraclass correlation coefficient of 0.67 (p = 0.003) between visits. No significant correlation between slope 2 StO2 and FMD or PRH was observed on visit 1 (r = -0.04, p = 0.89 and r = -0.30, p = 0.23, respectively) or visit 2 pre-exercise (r = -0.28, p = 0.25 and r = -0.31, p = 0.20, respectively). Compared to pre-exercise, FMD decreased immediately post-exercise (p < 0.001) and then increased 1.5 h post-exercise (p < 0.001). No significant change was detected for slope 2 StO2 (p = 0.30) or PRH (p = 0.55) following HIIE. Conclusion: In adolescents, slope 2 StO2 can be measured reliably, however, it is not correlated with FMD or PRH and does not follow the acute time course of changes in FMD post-exercise. Hence, the use of slope 2 StO2 as a surrogate measure of vascular function in youth must be refuted

    Effects of high-intensity interval training on the vascular and autonomic components of the baroreflex at rest in adolescents

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    This is the author accepted manuscript. The final version is available from Human Kinetics via the DOI in this recordPurpose: In a sample of healthy adolescents, we aimed to investigate the effects of high intensity interval exercise (HIIE) training and detraining on baroreflex sensitivity (BRS) and its vascular and autonomic components at rest Methods: Nineteen volunteers were randomly allocated to: 1) four weeks HIIE training performed three times per week; or 2) a control (CON) condition with no intervention for the same duration as HIIE training. PRE, POST and following two weeks of detraining (DET) resting supine heart rate and blood pressure were measured and a cross-spectral method (LFgain) was used to determine BRS gain. Arterial compliance (AC) was assessed as the BRS vascular component. LFgain divided by AC (LFgain/AC) was used as the autonomic determinant of BRS. Results: HIIE training was completed with 100% compliance. HIIE did not change resting LFgain (P=0.66; effect size (ES)=0.21), AC (P=0.44; ES=0.36) or LFgain/AC (P=0.68; ES=0.19) compared to CON. Conclusion: Four weeks of HIIE training does not change BRS and its autonomic and vascular determinant in a sample of healthy adolescents at rest

    Designing tools to predict and mitigate impacts on water quality following the Australian 2019/2020 wildfires: Insights from Sydney's largest water supply catchment

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    The 2019/20 Australian bushfires (or wildfires) burned the largest forested area in Australia's recorded history, with major socio‐economic and environmental consequences. Among the largest fires was the 280,000 ha Green Wattle Creek Fire which burned large forested areas of the Warragamba catchment. This protected catchment provides critical ecosystem services for Lake Burragorang, one of Australia's largest urban supply reservoirs delivering ~85 % of the water used in Greater Sydney. WaterNSW is the utility responsible for managing water quality in Lake Burragorang. Its postfire risk assessment, carried out in collaboration with researchers in Australia, the UK and USA, involved i) identifying pyrogenic contaminants in ash and soil; ii) quantifying ash loads and contaminant concentrations across the burned area; and iii) estimating the probability and quantity of soil, ash and associated contaminants entrainment for different rainfall scenarios. The work included refining the capabilities of the new WEPPcloud‐WATAR‐AU model (Water Erosion Prediction Project cloud‐Wildfire Ash Transport And Risk‐Australia) for predicting sediment, ash and contaminants transport, aided by outcomes from previous collaborative post‐fire research in the catchment. Approximately two weeks after the Green Wattle Creek Fire was contained, an extreme rainfall event (~276 mm in 72 h), caused extensive ash and sediment delivery into the reservoir. The risk assessment informed on‐ground monitoring and operational mitigation measures (deployment of debris‐catching booms and adjustment of the water supply system configuration), ensuring the continuity of safe water supply to Sydney. WEPPcloud‐WATAR‐AU outputs can prioritize recovery interventions for managing water quality risks by quantifying contaminants on the hillslopes, anticipating water contamination risk, and identifying areas with high susceptibility to ash and sediment transport. This collaborative interaction among scientists and water managers, aimed also at refining model capabilities and outputs to meet managers’ needs, exemplifies the successful outcomes that can be achieved at the interface of industry and science
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